Rat Model to Investigate the Effect of Oleuropein on Cardiac Tissue in D-Galactose-Induced Aging

Abstract

Background: D-Galactose (D-Gal) is naturally produced in the body and significantly impacts the aging process and the pathogenesis of some diseases. Objectives: This study aimed to investigate the protective impact of oleuropein (OLE) against D-Gal-induced heart aging in rat models. Methods: Forty Wistar male adult rats were categorized into five groups. The primary group was given distilled water, and the second group was given D-Gal at 100 mg/kg intraperitoneally. The rats in groups 3 to 5 were orally administered D-Gal (100 mg/kg) once a day. These groups were simultaneously subjected to dosages of OLE (20, 40, and 80 mg/kg, respectively) via the oral route. All treatments were administered once a day for eight consecutive weeks. Approximately 24 hours after the final treatment, the rats were euthanized, and serum and heart specimens were collected. The levels of protein carbonyl (PC), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), and the expression of proliferator-activated receptor-gamma coactivator (PGC-1α) and sirtuin 1 (SIRT1) genes in heart tissue were determined. Heart tissue was preserved in 10% formalin for hematoxylin and eosin (H&E) and histological examination. Results: The findings showed that D-Gal significantly decreased GPx, catalase (CAT), and SOD, glutathione (GSH) levels, as well as SIRT1 and PGC1 expression within the heart tissue (P < 0.05). Additionally, D-Gal significantly increased PC and MDA levels and serum cardiac markers [creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), aspartate aminotransferase (AST), and cardiac troponin I (cTnI)] (P < 0.05). The protective effect of OLE was confirmed by histological examination. Conclusions: The study demonstrated that OLE dose-dependently reduced heart lesions caused by D-Gal. The findings suggest that the protective effect of OLE is through the reduction of oxidative damage.